Double ring



FIG. 1 is a top plan view of a double ring showing my new design;

FIG. 2 is a side elevational view thereof, both sides being the same;

FIG. 3 is an edge elevational view thereof, both edges being the same;

FIG. 4 is a bottom plan view thereof; and

FIG. 5 is an exploded perspective view thereof. 

The ornamental design for a double ring, substantially as shown and described. 